LOD Recipe - Morph targets
Run the editor and open the content browser.
Click Add New / Simplygon / LOD Recipe and type a name.
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Open the LOD Recipe editor by double clicking the new asset.
Add a skeletal mesh using Add Mesh in the toolbar.
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By default three LODs would be populated using the Reduction Pipeline with their Settings / Reduction Settings / Reduction Target Triangle Ratio set to 0.5, 0.25, 0.125 respectively.
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Go to Allow Morph Targets Tab.
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Check Allow Morph Targets for each LOD you wish to keep morph targets on.
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Save the asset.
Press the Build button in the toolbar to generate the LOD chain with morph targets.